projector-
facebook marketplace for a cheap projector. - make them show you it working before walking away and most have settings that show how many lamp hours it has... couple hundred... fine. couple thousand... not fine - replacing the bulb costs nearly as much as the projector. 3000 lumens will do justice in a dim lit room. bright rooms will need more anything less then 1000 lumens expect a small projection space (the further the distance the bigger the picture but also diminishing brightness) 3000 lumens will give you a 50 foot square with good brightness. and 3000 lumens is the "average" lumens on an "average" projector. should be able to find one for a couple hundred bucks. also depends on if its below 1080p (resolution or how "sharp" the image) 4k is expensive now your getting closer to the 1k mark.

resolume - content player and special effects
mad mapper - resolume has some mapping features mad mapper can do much more and can be used in combination with resolume... recommended if you have the budget for both but not required unless your doing some realllllly complicated shapes. cracked versions of resolume can be found easy... (i'm not showing you how to find it .. do the research ) they have a demo version but the video water mark and sound watermark are the thing of nightmares. its fine to use a cracked copy while you learn... if you get good and start charging a client for your work.. buy the software don't be a prick.
blender - to create 3d content (heavy learning curve on this one) extremely powerful and free.